Telephone.



F. LACROIX.

TELEPHONE.- APPLlcATxoN FILED APR. s4., uns.4

'Pam-,ed Nov. 6; 1917.

@ggg

FRED LneROIX, or NEW YORK, N. Y., AssIGNoR 0F ONE-HALE 'ro or NEW YORK, N. Y. l.

TELEPHONE.

Application filed April 14, 1916. Serial N0. 91,17.

To all r-whom t may concern Be it known that I, FRED LACROIX, a citizen of the United States, and a resident of New York, in the county of vNew York and State of-New York, have invented certain new 4and useful Improvements inA Telephones, of which the following is a description. i 4

In the sending of ltelephone messages ordinarily the charge is made against the subscriber at the sending end of the line, and the unauthorized use of the. instrument in sending messages has caused considerable friction between the subscriber and the pany in adjusting his account. The object of the present invention is to provide means whereby a subscriber can control the sending of messages through his instrument without interfering with the receipt of incomingmessages.

Locking devices have been provided for Ysecuring the instrument against unauthorized use, but such devices are objectionable as they prevent the use of the instrument to receive incoming messages, as well as to prevent the initiation of out-going messages. The present invention avolds this objectionable feature, for the control only exstruction and arrangement of parts hereintends to the initiation of out-going messages,

and in no way effects the receipt of incoming messages and the reply to the same.

The invention consists in the novel conafter described, pointed out in the appended f claims, and illustrated by the accompanying drawing.

The figure in the drawing is a diagrammatic representa-tion ofL a subscribers telephone embodying the invention.

Leading from the central station to th-e subscribers station are the lines l and 2 forming a normally closed ringing circuit through the bell a and coil of the magnet b. Leading from the line 2 is the branch 3 orming an electric path through the transmitter c andthe receiver d, the continuity of this path being controlled by the switchhook of the receiver in the usual manner. The branch 3 terminates in the switch e positioned to bev attracted by the electromagnets and f when the latter are energized. The switch is normally pulled away from the magnets by the spring g. The coil of the magnet f terminates at one end in the contact 4 in a position to engage the Specification of Letters Patent.

' the receiver rammen Nev. c, 191'?.

switch e `when the lat-ter energized magnets, and at the other end the coil terminates in the line r1. Bridging the magnets and the switch c is the line loop 5 leading from the branch 3 to the linel. In the line loop 5 are thecontacts 6 adaptedk to be closed by the key it. A casing in-v closesthe magnets t, f,the switch e, and the contacts 6, and is provided with ay hole to admit the key It.

The operationv isl as follows: Vhen the ringing circuit is closed at the centra-istation through the wires l, 2, the call bell a is sounded at the subscribers station and the magnet Z) is energized and the switch e is moved by the responding to the call the subscriber lifts the 'receiver and the upward movement of the released switch-hook completes the speaking circuit through the line 3 at that point; The operator at the central station on obtaining the response through thelifting of at the subscribers station, cuts out the alternating or ringing current and simultaneously turns in the direct or speaking current. When the ringing current is broken the magnet Z) is denergized, but the immediate passage of the direct currentV through the magnet f causes the latter to hold the switch c against the-contact 4; and sustains the speaking circuit at that point. When the receiver is returned to its hook the speaking circuit is broken, and as the magnet f is denergized the switch e is pulled away b v its spring and the speaking circuit is also broken at that point. The initiation of calls at the central station is not affected b v the subscribers controlling means at his station.

Should it be desired to initiate a call at the subscribers station the keyl lz is positioned to closel the break between the contacts 6 in the bridging loop 5. When the receiver is lifted the upward movement of its hook completes the circuit with the central station through the leads l., 2, the the branch 3, and the bridging loop. On.

receiving the signal the operator makes the is done no circuit can be established between the subscribers instrument and the central station. Should the transmitter be lifted and its hook moved to close the circuit. at that point, the circuit to the central station would still be incomplete through the break between the contacts 6, and by the break caused by the switch e being pulled away from the contact 4L. With the key h in place to close the break between the contacts 6 the circuit to the central station could be readily established. By controlling the Yhandling of the key 7L the subscriber can control the sending of messages from his station. rlfhe key and key-hole can be provided with the usual guards to prevent the use of false keys.

' laving thus described my invention, what I claim and desire to secure by Letters Patent is:

l. In a telephone, a circuit from the central station including at the subsori'bers station a. normally closed ringing circuit and a normally open talking circuit, a normally open switch in the talking circuit, an electromagnet in the ringing circuit when energized operating to move said switch to close the talking circuit at that point, a second electromagnet in the talking circuit when energized operating to hold said switch to close the talking circuit at that Copies ci this patent may be obtained for ve cents each,

`key-hole into the casing point, a line loop bridging the talkingcircuit around said switch and around the electromagnet in the talking circuit, and removable means or making and breaking the talking circuit through the bridging loop.

2; ln a telephone7 a circuit from the central station including at the subscribers station a normally closed ringing circuit and a normally open talking circuit, a normally open switch in the talking circuit, an electromagnet in the ringing circuit when energi'Zed operating to move said switch to close the talking circuit at that point, a second clectromagnet in the talking circuit when energized operating to hold said switch to close the talking circuitat that point, a line loop bridging the talking circuit around said 1 switch and around the elcctromagnet in the talking circuit, said bridging loop having separated contacts, acasing inolosing the electromagncts', switch and contacts of the bridging loop and provided with a key-hole, and key adapted to be inserted through the L to electrically connect the' contacts of the bridging loop.

In testimony whereof l hereunto my signature in the presence of two witnesses. FRED LACBOX.V Witnessesz Guo. P. MonnLL, NiLs Horan by addressing the Commissioner of Entente,

Washington, D. C. 

